<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>

<body>
    <form action="/add?_csrf=<%=csrf%>" method="POST">
        <!-- 也可以使用隐藏的表达域进行post
            <input type="hidden" name="_csrf" value="<%=csrf%>"/>
         -->
        用户名：<input type="text" name="username" /><br><br>
        密码：<input type="password" name="password" /><br><br>
        <button type="submit">提交</button>
    </form>
</body>

</html>